Roller mount for ladders



May 27, 1969 R. D. DAVIS ET AL 3,446,309

ROLLER MOUNT FOR LADDERS Filed June 1, 1966 Ralph D. Davis John E.Po/ley IN VENTORS Atbmq:

United States Patent Fla.

Filed June 1, 1966, Ser. No. 554,392 Int. Cl. E06c /32, 7/42; E04g 5/02US. Cl. 182-429 10 Claims ABSTRACT OF THE DISCLOSURE A roller mountparticularly adapted for folding ladders including a caster-type wheeldepending from a horizontal base. A first side plate is fixed to thebase and projects vertically therefrom for engagement against one sideof a ladder leg. A second plate is positioned laterally of the firstplate so as to lie against the second side of a ladder leg, the secondplate being free of the base and selectively movable toward the firstplate so as to clamp a received ladder leg therebetween by front andrear sets of transverse bolts positioned both forward and rearward ofthe front and rear edges of the ladder leg so as to lie against theseedges and further stabilize the mount relative to the leg.

The instant invention is generally concerned with ladders, and moreparticularly relates to an attachment in the nature of a roller mountwhich is releasably engageable with a leg of a folding ladder so as to,in conjunction with three similar mounts, increase the mobility thereof.

It is a primary object of the instant invention to provide a rollermount which is uniquely adapted for releasable clamping engagement witha leg of a folding ladder, it be ing contemplated that four such mountsbe used in each instance, so as to provide a ladder capable of beingquickly and easily rolled from location to location.

Another important object of the instant invention resides in theincorporation of means whereby the roller mount can accommodate itselfto various minor irregularities in the dimensions of a ladder legwithout detracting from the positive clamped engagement necessary toprovide a stable connection.

Further, it is a significant object of the instant invention to providea roller mount for ladders which is of a relatively simple constructionpossessing a high degree of structural stability.

Basically, the roller mount of the instant invention comprises a casterwheel swivelly engaged with and depending from a base plate which inturn has two laterally spaced upwardly projecting clamping platesthereon. These clamping plates are to receive the lower end of a ladderleg therebetween with the vertical plates subsequently being drawntogether in clamping engagement with the opposite sides of the leg so asto effect the desired affixing of the mount to the corresponding leg.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

FIGURE 1 is a perspective view of the lower portion of a conventionalfolding ladder having a roller mount, in accordance with the instantinvention, aflixed to the lower end of each of the legs thereof;

FIGURE 2 is an enlarged partial elevational view taken substantially ona plane passing along line 2-2 in FIG- URE 1; and

FIGURE 3 is an enlarged cross-sectional view taken substantially on aplane passing along line 3-3 in FIG- URE 1.

Referring now more specifically to the drawings, reference numeral 10 isused to generally designate the roller mount of the instant invention.As will be appreciated from FIGURE 1, four such mounts are to beutilized in conjunction with a folding ladder 12, one being rigidly,although releasably, afixed to the lower end of each of the ladder legs14.

Each of the roller mounts 10 includes a relatively large wheel 16rotatably mounted between the depending sides 18 of a saddle 20 with thesaddle 20 in turn having the fiat or bight portion 22 thereof swivellyaffixed to an enlarged fiat mounting plate or base 24 by means of asuitable shaft and ball bearing connection 26 of any appropriate typeused in conventional caster wheel units.

Each roller mount 10 includes a pair of laterally spaced verticallyprojecting fiat clamping plates 28 and 29, these plates having parallelinclined front and rear edges generally conforming to the angle ofinclination of the legs of a folding or step ladder. The outer clampingplate 28 has a laterally directed flange 30 which overlies the base 24and is suitably bolted thereto by a pair of bolts 32, each provided witha suitable nut and lock washer 34. The inner plate 29, on the contrary,is a free floating plate not directly secured to the base. Thecorresponding ladder leg 14 is received between the vertical clampingplates 28 and 29 which are of a length greater than the depth of the leg14. Finally, the actual clamping of the leg 14, the lower end 36 thereofengaging the top of the base 24 directly over the wheel 16, is effectedby front and rear pairs of clamping bolts 38. Each of the bolts 38extends through the two spaced plates 28 and 29 with the head 40 thereofengaged against the outer face of the outer plate 28 and with a suitablenut, preferably in the nature of a wing nut 42 for easy manualmanipulation, threaded on the opposite end thereof into engagement withthe outer face of the inner plate 29 whereby, upon a tightening of thenuts 42 on all of the clamping bolts 38, an inward drawing of the plate29 will be effected and a corresponding rigid clamping of the lower endof the leg 14 achieved between the plates 28 and 29. While a high degreeof stability will be achieved through the engagement of the lower end ofthe leg 14 on the base plate 24 and the clamping of the side plates 28and 29 thereagainst, it is also contemplated that the forward and rearpairs of clamping bolts 38 be so located as to, whenever possible,engage directly against the edges of the leg 14.

With particular reference to FIGURE 1, it will be appreciated that eachof the plates 28 and 29 has three sets of bolt-receiving holes 44, oneadjacent the front edge, one adjacent the rear edge, and one just inwardof the rear set. The three sets of holes 44 are of significance inenabling the use of the same mount 10 on both of the wider front ladderlegs, using the front and rear sets of holes 44, and the narrower rearladder legs, utilizing the front and intermediate sets of holes 44. Ineach instance, the holes 44 of each set are orientated on an inclinedline generally corresponding to the angle of the ladder legs.

In order to provide the stability necessary when the ladder is actuallybeing used, suitable conventional caster lock units 46 can be providedgenerally on the two mounts 10 associated with the front ladder legs.Further, while it is preferable that the plate 29 not have a mountingflange, with this plate 29 being free of the base 24 and acting so as torigidly clamp the lower portion of the corresponding leg 14 to thesingle plate 28 which is in turn fixedly locked to the base 24, it ispossible to also provide the plate 29 with a mounting flange and rely onan inward flexing of the plates 28 and 29 to effect the desiredclamping. In either arrangement, the

wing nuts 42 are positioned on the inside of the ladder so as to avoidany unnecessary projections which might scrape walls, etc.

From the foregoing, it will be appreciated that a highly unique rollermount has been provided which mount, in conjunction with sufiicientsimilar mounts so as to accommodate all of the legs of a particularladder, provides a convenient manner of facilitating the use, handlingand moving of such ladder without in any way affecting the basicoperation of the ladder or interfering with the use of the ladder in themanner of a conventional ladder.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed.

What is claimed as new is as follows:

1. For use in conjunction with a folding ladder, a roller mount usablein conjunction with at least one similar mount, said mount beingengageable with a leg of the ladder, said mount including a horizontalbase for the supporting reception of the lower end of the ladder legthereon, roller means, means rotatably mounting said roller means onsaid babse vertically therebelow, a pair of laterally spaced verticalplates positioned over said base and projecting upwardly therefrom forthe reception of a base supported ladder leg therebetween, the loweredge of one of said plates being rigidly fixed to said base, and meansfor selectively drawing the second of said plates laterally toward saidone plate for effecting the clamping of a ladder leg receivedtherebetween.

2. The structure of claim 1 wherein said means for selectively drawingthe second plate laterally toward the one plate comprises at least twobolts engaged with and extending perpendicularly between said pair oflaterally spaced plates, said bolts being laterally spaced from eachother and defining, in conjunction with the plates, an upwardly openingsocket for the reception of a ladder leg therein positioned inengagement with said horizontal base.

3. The structure of claim 2 wherein said second plate has a free loweredge independent of and movable relative to said horizontal base.

4. The structure of claim 3 including a second bolt located parallel to,above and slightly laterally offset from each of the first two bolts soas to present the upwardly opening socket at a slight inclination togenerally conform to the angle of inclination of a folding ladder leg.

5. The structure of claim 4 wherein said plates each has three sets ofbolt-receiving holes defined therein, said plates having generallyvertical front and rear edges, said sets of bolt-receiving holesincluding a first set adjacent the front edge of each plate, a rear setadjacent the rear edge of each plate, and an intermediate set justinward of the rear set and substantially closer to the rear set than thefront set for the accommodation of ladder legs of various depths.

6. The structure of claim 2 including a second bolt located parallel to,above and slightly laterally offset from each of the first two bolts soas to present the upwardly opening socket at a slight inclination togenerally conform to the angle of inclination of a folding ladder leg.

7. The structure of claim 6 wherein said plates each has three sets ofbolt-receiving holes defined therein, said plates having generallyvertical front and rear edges, said sets of bolt-receiving holesincluding a first set adjacent the front edge of each plate, a rear setadjacent the rear edge of each plate, and an intermediate set justinward of the rear set and substantially closer to the rear set than thefront set for the accommodation of ladder legs of various depths.

8. The structure of claim 1 wherein said second plate has a free loweredge independent of and movable relative to said horizontal base.

9. A ladder leg and roller mount therefor, said ladder leg including alower portion having a fiat lower edge, front and rear edges, andopposed substantially planar faces, said mount including a base portionunderlying, receiving and supporting the ladder leg lower edge, a firstvertical plate rigid with said base portion and projecting verticallytherefrom juxtaposed one of said ladder leg side faces, a second plateparallel to and laterally spaced from the first plate juxtaposed thesecond side face of said ladder leg, at least one bolt engaged with andextending between said plates immediately forward of the front edge ofsaid ladder leg, and a nut operably threaded on said bolt for effectinga lateral movement of the second plate toward the first plate and aclamping of the ladder leg therebetween, a second bolt engaged with andextending transversely between said plates immediately rearward of therear edge of said ladder leg, a nut operably threaded on said secondbolt for effecting a selective movement of the second plate laterallytoward the first plate and a clamping of the ladder leg therebetween,and a roller affixed to and depending from said base portion.

10. The structure of claim 9 wherein said second plate terminates in alower edge independent of and freely movable relative to said baseportion, said second plate lower edge being positioned in upwardlyspaced relation to said base portion, and third and fourth bolts andcooperating nuts positioned above the first and second bolts andsimilarly extending transversely across the front and rear edges of saidladder leg for assisting in the clamping movement of the second platetoward the first plate.

References Cited UNITED STATES PATENTS 1,085,693 2/1914 McKinney 16302,371,460 3/1945 Needham 182108 1,171,569 2/1916 Wanda 1630 2,800,6797/1957 Schultz 16-30 2,782,045 2/1957 Hulbert 16-30 1,017,799 2/ 1912Read 1630 FOREIGN PATENTS 310,109 12/1955 Switzerland.

BOBBY R. GAY, Primary Examiner.

DORIS L. TROUTMAN, Assistant Examiner.

U.S. c1. X.R. 161 31; 1s2-10s

